The general operation of fueling aircraft for both military and commercial operations has become relatively uniform throughout the various aircraft service industries. Basically, fuel is supplied by fuel trucks having large fuel reservoirs and independent fuel pumping apparatus together with extended large diameter fueling hoses. The fuel hoses terminate in a fueling nozzle which includes a hand operated fueling valve often referred to as a poppet or poppet valve. The fueling nozzle valves are typically opened and closed by the manipulation of a rotating lever or crank. Correspondingly, the aircraft includes a fuel line which terminates in an externally accessible fueling port for receiving fuel. The fueling port includes an adaptor configured to receive and engage the fueling nozzle in a positive interlock attachment for safety of operation. The typical fueling adaptor used on most aircraft today includes an annular cylindrical portion extending outwardly from the fuel port which in turn defines a plurality of interlock notches and adaptor lugs for engaging corresponding notches and lugs within the fueling nozzle.
The operation of fueling an aircraft involves bringing a fuel truck in close proximity to the aircraft and thereafter playing out a quantity of fueling hose having a fueling nozzle at the end which is then engaged with and secured to the aircraft adaptor. Once engagement is complete, the fuel nozzle valve is opened and the operator initiates the pumping of fuel into the aircraft. At the completion of the fuel transfer, the valve is then closed and the pumping operation is terminated. Finally, the nozzle is removed from the adaptor and the hose is wound back upon the fueling truck completing the operation.
The extremely volatile and potentially explosive quality of the aircraft fuels used necessitate the careful and safety conscious operation of aircraft refueling. The need to maintain safe operation is rendered more difficult in the typical fast pace action of modern high traffic aircraft facilities and the pressure for rapid turnaround of aircraft while on the ground. Further, aircraft are generally most likely to be refueled in weather exposed circumstances subjecting the fueling operators to a variety of weather conditions. These constraints and difficulties by their very nature increase the ever present danger of fuel spill mishaps and the corresponding danger they present.
To help ensure the safety of aircraft fueling operations, various safety features are required in the design and structure of fueling equipment. In particular, the aircraft fueling nozzle is required to provide and maintain various safety features. The most prevalent of such safety features is found in two basic safety interlocks which the apparatus must possess. The first interlock is operative when the flow valve of the nozzle (often called the poppet) is in a closed condition. This interlock prevents the opening of the flow valve unless and until the fuel nozzle is properly engaged and interlocked with an airplane fueling adaptor. This prevents inadvertent opening of the fuel valve and fuel spillage when the nozzle is not connected to an aircraft. The second basic interlock is operative when the valve is in an open condition and the nozzle is engaged with a fueling adaptor during aircraft fueling operations. The interlock active under fueling conditions prevents the removal and disengagement of the fueling nozzle from the aircraft adaptor unless and until the fueled valve has been closed. This, of course, is utilized to prevent the disastrous possibility of inadvertent removal or accidental disengagement of a fueling nozzle from an aircraft while the high pressure fuel pump on the fueling truck is operative.
While safety of operation is essential and foremost in the design and maintenance of fuel nozzles, practitioners in the art also endeavor to enhance the use and operation of such nozzles in aircraft fueling by making the nozzles lighter and easier to handle and operate.
In response to these needs, practitioners in the art have provided a variety of aircraft fueling nozzle designs. For example, U.S. Pat. No. 2,679,407 issued to Badger, Jr. sets forth a NOZZLE FOR FUELING AND DRAINING TANKS having a curved tubular housing securable to the open end of a fuel line at one end and supporting a movable poppet valve and engaging mechanism at the opposite end. An elongated poppet rod extends downwardly from the poppet through an aperture formed in the curved tube. The poppet rod is coupled to a multiply linked crank mechanism which in turn is secured to an external crank lever operable by the user to open and close the poppet valve.
U.S. Pat. No. 4,030,524 issued to McMath, et al. sets forth a COUPLER FOR ATTACHMENT TO AN ADAPTOR together with apparatus which requires that the adaptor must be disposed within the coupler in the position of locking engagement before a rotatable shaft within the coupler may be rotated to initially lock the adaptor and coupler. The coupler includes a poppet valve which opens a valve in a passage in the adaptor when the coupler has properly engaged the adaptor.
U.S. Pat. No. 5,273,071 issued to Oberrecht sets forth DRY DISCONNECT COUPLINGS comprising an adaptor connected to a liquid conduit and a coupler connected to another liquid conduit. The adaptor and coupler each have poppets which seal passageway outlets thereof when they are disconnected. When connected, means are provided for simultaneously opening the poppets by displacing them with their end faces in contiguous relation.
While the foregoing described prior art devices have provided improvement in the art and, in some instances, enjoyed commercial success, there remains nonetheless a continuing need in the art for evermore improved effective, efficient and easy to use aircraft fueling nozzles.